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51.
Maeda A Ohguro H Nabeta Y Hirohashi Y Sahara H Maeda T Wada Y Sato T Yun C Nishimura Y Torigoe T Kuroki Y Sato N 《European journal of immunology》2001,31(2):563-572
Cancer-associated retinopathy (CAR) is a rare paraneoplastic syndrome, and the recoverin-specific autoantibody is suggested to contribute to the pathogenesis of retinopathy, including apoptosis of retinal cells. Because it is known that CAR(+) cancer patients have a preferable prognosis, we hypothesized that aberrantly expressed recoverin in cancer cells can become a target of cytotoxic T lymphocytes (CTL). Here we tested nine recoverin-derived HLA-A24-binding peptides for their capacity to elicit antitumor CTL. We observed recoverin-specific CTL responses in two HLA-A24(+) CAR(+) cancer patients. In addition, the CTL responses were obtained from three of ten CAR(-) cancer patients and two of six healthy individuals. The CTL precursor frequency of CAR(+) cancer patients and that of CAR(-) cancer patients was higher than that of healthy individuals. Of nine recoverin peptides, R49 (QFQSIYAKF), R49.2 (QFQSIYAKFF), and R64 (AYAQHVFRSF) were discovered to induce the peptide-specific CTL. Taken together, our present data suggest that peripheral activation of recoverin-specific antitumor CTL is likely to contribute to the preferable prognosis of CAR(+) cancer patients. Moreover, in cases other than CAR(+) cancer patients, recoverin may offer the opportunity to design epitope-based immunotherapeutic approaches for treating HLA-A24(+) cancer patients with a recoverin-expressing tumor. 相似文献
52.
In most cases, while schwannoma is sporadically manifested as a single benign neoplasm, the presence of multiple schwannomas in one patient is usually indicative of neurofibromatosis 2. However, several recent reports have suggested that schwannomatosis itself may also be a distinct clinical entity. This study examines an extremely rare case of probable schwannomatosis associated with intracranial, intraspinal and peripheral involvements. A 63-year-old woman presented with a seven-year history of palpable lumps on both sides of the supraclavicular area and hearing impairment in both ears. On physical examination, no skin manifestations were evident. Facial sensory change, deafness in the left ear and decreased gag reflex were revealed by neurological examination. Magnetic resonance imaging revealed multiple lesions of the trigeminal nerves, acoustic nerves, lower cranial nerves, spinal accessory nerve, brachial plexuses, and spinal nerves. Pathological examination of tumors from the bilateral brachial plexuses, the spinal nerve in the T8 spinal position and the neck mass revealed benign schwannomas. Following is this patient case report of multiple schwannomas presenting with no skin manifestations of neurofibromatosis. 相似文献
53.
We investigated the effect of beta-adrenergic stimulation on the heart rate and QT interval in syncope children with or without coexisting ventricular arrhythmias (VA). Of the 24 children who presented with syncope or presyncope and showed negative tilt test, 13 were classified into a group with VA and the remaining 11 without VA. The provocative test was performed in bolus infusion and continuous infusion. RR, QT, and QTc intervals on routine 12-lead surface electrocardiogram were obtained during each stage of isoproterenol infusion. In all cases, malignant ventricular arrhythmia and syncope were not induced by isoproterenol provocative test. RR and QT intervals were shortened and QTc intervals were prolonged as the isoproterenol dose was increased in both groups and methods. The QTc interval reached its peak level after the bolus injection of 1.0 microgram and during the continuous infusion of 0.03 microgram/kg/min. The two groups showed no significant difference in the QTc interval change according to the infusion methods. This study indicates that changes in the heart rate and QT interval by beta-adrenergic stimulation were not different according to the coexisting ventricular arrhythmias in syncope children with negative head-up tilt test. 相似文献
54.
目的 探讨能否直接利用肿瘤细胞膜进行表皮生长因子受体 (Epidermalgrowthfactorreceptor,EGFR)催化活性检测。方法 首先筛选出EGFR基因表达水平相对较高的细胞株MDA MB 2 31,通过差速离心制备细胞膜 ,采用Westernblotting检测EGFR催化磷酸化的程度。结果 底物被磷酸化 ,加入特异性拮抗剂AG14 78后 ,磷酸化被抑制。结论 利用肿瘤细胞膜检测EGFR活性的设想是成立的 ,并且其方法简便、经济。 相似文献
55.
本文研究丁敌枯双对BALB/C雄性小鼠生殖细胞分裂比率及精原细胞染色体畸变的影响。将实验小鼠随机分为三组,即实验组(敌枯双组),阳性对照组(环磷酰胺组)和阴性对照组(双蒸水组)。结果发现:敌枯双能明显诱发精原细胞多倍体率和裂隙率增加,抑制终变期/中期Ⅰ和中期Ⅱ细胞的减数分裂比率,促进精原细胞有丝分裂比率。实验结果还提示:在遗传毒理检测中亚急性实验是必要的,并对实验结果进行了初步讨论。 相似文献
56.
57.
碘化钠对人甲状腺上皮细胞TNF-α、IL-1β分泌的影响 总被引:2,自引:0,他引:2
为研究碘化钠 (NaI)对人甲状腺上皮细胞 (TEC )分泌细胞因子TNF α和IL 1β的影响 ,以探讨碘在GD病 (GD )发病中的可能机制 ,取手术切除的GD病患者甲状腺组织和甲状腺腺瘤患者瘤旁正常甲状腺组织 ,进行细胞培养。以不同浓度的NaI (10 8~ 10 3 mol/L )刺激单层培养的甲状腺细胞 ,采用放射免疫测定技术测定刺激前后甲状腺细胞培养上清液中细胞因子TNF α和IL 1β的含量。同时以透射电镜观察NaI刺激后甲状腺细胞的形态学改变。结果 :(1)正常甲状腺细胞能分泌少量的TNF α和IL 1β。GD的甲状腺细胞TNF α和IL 1β的分泌量与正常TEC相比显著增加 (P <0 0 1) ;(2 )当NaI浓度为 10 8~10 3 mol/L时 ,正常人甲状腺细胞TNF α、IL 1β的分泌量与 0mol/L组相比无显著性差异 (P >0 0 5 ) ;透射电镜示正常甲状腺细胞无损伤型改变 ;(3)当NaI浓度为 10 6~ 10 3 mol/L时 ,GD甲状腺细胞TNF α的分泌量显著增加 (P <0 0 5 ) ;当NaI浓度为 10 8~ 10 3 mol/L时 ,GD甲状腺细胞IL 1β的分泌量显著增加 (P <0 0 5 )。NaI浓度超过 10 6mol/L时 ,透射电镜示GD甲状腺细胞出现损伤型改变。表明高浓度的碘不仅造成GD甲状腺细胞的直接损伤 ,而且可以增加甲状腺细胞细胞因子TNF α和IL 1β的分泌 ,特别是在GD甲状腺细 相似文献
58.
Brazilin and haematoxylin, plant pigments, were examined for their effects on the Bovine-Lens aldose reductase (LAR)-activity. About 50% inhibition was observed in a concentration of 10 (-4) M-brazilin and 10 (-4) M-haematoxylin, and above 95% inhibition was observed in a concentration of 10 (-3) M-brazilin and 10 (-3)M-haematoxylin. In order to determine the type of inhibition, kinetic studies were also conducted with brazilin and haematoxylin, in which both were found to be noncompetitive inhibitors. 相似文献
59.
运动训练对慢性应激大鼠β—内啡肽分泌的影响 总被引:6,自引:0,他引:6
目的:探讨运动训练对慢性应激大鼠β-内啡肽(β-EP)分泌的变化。方法:对大鼠进行为期8周的不同负荷运动训练,并在运动训练后期给予3周的冷刺激,测定大鼠下丘脑和血清中β-EP的含量。结果:(1)经过3周的冷应激后,大鼠产生显著的身心变化,下丘脑和血清β-EP的含量均显著升高,从而表明冷应激可使机体β-ED的合成和释放增多。(2)经过8周的运动训练后,大鼠下丘脑β-EP含量显著升高,血清β-EP含量显著下降;而对运动训练的大鼠施加冷刺激后,大鼠下丘脑和血清中β-EP含量显著低于应激组,以中等负荷运动训练组最为明显。结论:运动训练可以减少内源性β-EP的释放,有效对抗大鼠机体对冷刺激产生的应激反应,维持机体在应激状态下内分泌功能的稳定。 相似文献
60.
目的 :研究肾综合征出血热 (HFRS)多尿期肾图的变化及其意义。方法 :静脉注射 1 31 I-邻碘马尿酸钠 (1 31 I- OIH) 3.7×10 9Bq(10 μCi) ,用闪烁照相法描记 15 min,通过电子计算机自动处理 ,得出肾图的各项参数。结果 :2 0例受检者均已进入多尿期 ,2 4h尿量在 2 0 0 0 ml以上 ,血尿素氮 (BUN)已正常或接近正常 ,但肾图却明显异常 ,表现为半排时间 (TC1 /2 )延长 (>8min) ,15min残留率 (C1 5 /b)超过 5 0 % ,肾脏指数大多低于 45 % ;同期作尿β2 -微球蛋白 (β2 - m )测定 ,也明显高于正常 ;8例作发射型电子计算机扫描 (ECT)检查 ,肾小球滤过率 (GFR)和有效肾血浆流量 (ERPF)分别为 (4 0 .8± 2 1.2 ) ml/min和 (35 0 .8± 10 2 .1) ml/min,均明显低于正常 (P<0 .0 1)。结论 :HFRS患者多尿期肾图大多呈排出不良和功能受损的图形 ,表明该期肾功能以及肾血流量尚未恢复正常 ,对症治疗仍需继续。 相似文献